I picked up this set of helping hands at the hobby shop the other day for $14. You can pick it up online on Amazon as well. It features two alligator clamps and a magnifying glass, all on adjustable arms that move in any direction. The base is pretty heavy, so it won’t move around on you. The whole thing feels very solid.
I have used it to hold several mates as I paint them. I had to wrap duct tape around one of the clamps, as it left marks on some of the softer minimate parts. I left the other one tape-free for a better grip. That one works very well for holding the chest peg while painting a set of legs.
The magnifying glass is surprisingly helpful for painting small details. The tightness of the joints are all adjustable, so you can make sure nothing moves while you are painting. I would have preferred the base to be a tiny bit heavier, as I have tipped it over once or twice, but overall it holds its ground.
Also, if you are planning on doing any light-up minimates, these arms are a God-send for soldering. I will be posting a video in the next few days on how to make a light-up Iron Man flight stand, and you can see this baby in action.